Suggest Treatment For Depression, Weight Gain And Drowsiness

Hi. I am 20 years & I am suffering from depression I am taking Serta 50mg in mrng n Olenz 2.5 & Oliptal DT in night. I am gaining weight & I feel much sleepy from the time I hav started this tablets n I am taking this tablets for past 2years but it dt hav any effect on me but still my doctor told me to continue same medicen but know I want to stop this tablets bco I feel sleepy & nt able to consentrate on studies. I want to do dental but my family is forcing me to do BA bco m nt well they think m nt worth to study dental bco m suffering from depression but I dt want change my side. Please guide me to stop my tablets n to take correct decisions regarding my studies that I am worth to to do dental or nt